GB2098907A

GB2098907A - Veneer peeling apparatus

Info

Publication number: GB2098907A
Application number: GB8114738A
Authority: GB
Original assignee: Hashimoto Denki Co Ltd
Current assignee: Hashimoto Denki Co Ltd
Priority date: 1981-05-14
Filing date: 1981-05-14
Publication date: 1982-12-01
Also published as: GB2098907B

Abstract

A veneer peeling apparatus having a veneer lathe (1) is provided which comprises a movable frame (11) pivotably connected to and movable with the veneer lathe (1) and a guide conveyor belt (12) supported by said movable frame (11) and extending from the upstream portion thereof into a hollow space between a knife block (3) and a nose-bar block (5) to define a first veneer discharge passage (16) above the inner surface of the knife block. A tenderizer (20) is supported by the movable frame (11) at the downstream end portion of the guide conveyor belt (12) and a fixed conveyor belt (25) is provided below the tenderizer for receiving the tenderized veneer to discharge the veneer out of the movable frame (11). <IMAGE>

Description

SPECIFICATION Veneer peeling aparatus The present invention relates to an apparatus for peeling veneer from a log by means of a veneer lathe.

A veneer lathe of this type is arranged in such a manner that when peeling of the veneer from the log is carried out continuously, the veneer lathe is advanced toward the axis of the log and also the cutting angle of the knife relative to the pheriphery of the log is adjusted. In a known apparatus, however, a belt conveyor for discharging the peeled veneer from the lathe is provided on a fixed frame and is arranged to be extensible in order to follow the movement of the veneer lathe. The running speed of the belt conveyor has to be controlled, preferably, in order to synchronize with the cutting speed of the veneer lathe.

However, the known extensible structure of the belt conveyor has been complicated making it difficult to precisely control the running speed thereof.

An object of the present invention is to provide a veneer peeling apparatus in which a belt conveyor for discharging a peeled veneer from a veneer lathe can follow the movement of the veneer lathe without extending the length thereof.

Another object of the present invention is to provide a veneer peeling apparatus of the type set forth above in which the belt conveyor for discharging the peeled veneer from the veneer lathe prevents a rolling-up of the peeled veneer and facilitates the smooth discharge thereof.

According to the present invention, there is provided an apparatus for peeling veneer comprising a veneer lathe having a knife, a nosebar, a knife block and a nose-bar block, the knife block and nose bar blocks defining a hollow space therebetween for discharging a veneer peeled from a log by said knife; a movable frame pivotably connected to said veneer lathe to move together with the movement of said veneer lathe, a guide conveyor belt supported by said movable frame and extending at an upstream portion thereof into said hollow space to define a first veneer discharge passage above the inner surface of said knife block; a tenderizer supported by said movable frame at the downstream end portion of said guide conveyor belt, and a fixed conveyor belt provided below said tenderizer for receiving the tenderized veneer to discharge said veneer outwardly of said movable frame.

In a preferred form of the present invention, the movable frame has an arm pivotably connected thereto at one end portion thereof which extends into said hollow space, the arm having a pulley at the other end portion thereof upon which said guide conveyor belt runs, said arm being elastically urged toward said nose-bar block.

Embodiments of the present invention will now be described, by way of example with reference to the accompanying drawings, in which: Figure 1 is a side view showing a veneer peeling apparatus according to the present invention, and Figure 2 is a partially sectioned side view showing the veneer peeling apparatus of Fig.

1.

Referring to a preferred embodiment of the present invention shown is Figs. 1 and 2, a veneer lathe 1 comprises a knife 2 held by a knife block 3 and a nose-bar 4 held by a nose-bar block 5. These blocks 3 and 5 are formed integrally with each other and are arranged in a known manner to peel a veneer 6 from a log 7 held by a spindle 8 which in turn is rotatably supported on a fixed frame 9.

These blocks 3 and 5 are movable toward the spindle 8 as the diameter of the log 7 is reduced as a result of peeling the veneer 6 and also movable in the vertical direction to adjust the cutting angle of the knife 2 relative to the periphery of the log 7. There is a hollow space 10 between the knife block 3 and the nose-bar block 5 through which the veneer 6 peeled from the log 7 is discharged.

According to an embodiment of the present invention, a movable frame 11 is pivotably connected to a veneer lathe 1 and, preferably, to the rear end portion of the knife block 3.

Extending from the movable frame 11 into a hollow space 10 between the knife block 3 and the nose-bar block 5 is a guide conveyor belt 1 2 which runs around triangularly arranged pulleys 1 3a, 1 3b, and 1 3c. The rear two pulleys 1 3b and 1 3c are supported on the movable frame 11 and the front two pulleys 1 3a and 13b are connected with each other by means of an arm 14, which is pivotably connected to the movable frame 11 and extends into a hollow space 10 of the veneer lathe 1. The arm 1 4 is urged upwardly about a shaft of the central pulley 1 3b by a tension spring 1 5 provided between the movable frame 11 and the arm 14, the upward movement of which is restricted by a front projection 1 4a on the arm contacting the inner surface of the nose-bar block 5.Thus, a relatively narrow veneer discharge passage 1 6 is defined between the front part of the conveyor belt 1 2 and the inner surface of the knife block 3. A tension roller 1 7 is provided at the rear upper part of the guide conveyor belt 1 2 to maintain the stretched condition of the conveyor belt 1 2 at any position of the arm 14.

The movable frame 11 also has a second conveyor belt 1 8 supported thereby and integrally moved therewith. The second conveyor belt 1 8 extends rearwardly from the front end portion of the movable frame 11 and defines a horizontal discharge passage 1 9 below the rear horizontal part of the guide conveyor belt 1 2. This horizontal discharge passage 1 9 becomes narrower in its vertical space as it goes rearwardly.

Provided also in the movable frame 11 at the rear ends of the guide conveyor belt 1 2 and the second conveyor belt 1 8 is a tenderizer 20, which comprises a rotary bar 21 having a small radius of curvature of about 10 mm to 20 mm and provided at the rear upper end of the second conveyor belt 1 8. The tenderizer 20 also comprises a small endless pressing belt 22 which runs around the pulley 1 3c at the rear end of the guide conveyor belt 12 and another pulley 23 having its shaft connected to a piston rod of an air cylinder 24. The pressing belt 22 is arranged in such a manner that when the air cylinder 24 is operated to extend the piston rod, the belt 22 is pushed toward the rotary bar 21.

Provided below the pressing belt 22 is a fixed discharge conveyor belt 25, the front end portion of which extends inwardly of the movable frame 11 and the rear end portion of which extends outwardly thereof. The movable frame 11 has rollers 26 at the rear lower end thereof, which rest on rails 27 on a floor 28 and allow the forward and rearward movement of the movable frame 11.

In operation, when the veneer lathe 1 is driven by a known method, the veneer 6 is peeled from the log 7 by the knife 2. At this time of peeling, usually, small cracks are partially developed in the veneer from the lower surface thereof, which causes an upward rolling of the veneer. In the apparatus of the present invention, since the guide conveyor belt 1 2 is provided above and adjacent to the inner surface of the knife block 3, the discharge of the peeled veneer 6 is facilitated in the downward and rearward direction by the conveyor belt 1 2 without the veneer rolling-up.After leaving the downwardly incined veneer discharge passage 16, the peeled veneer 6 is carried through the horizontal discharge passage 1 9 by the second conveyor belt 18 and also by the horizontal part of the guide conveyor belt 1 2. As the vertical space of the horizontal discharge passage 1 9 becomes narrower in the rearward direction, the peeled veneer 6 is gradually held by these blets 1 2 and 1 8 at the rear part thereof and carried to the tenderizer 20. Upon arriving at the tenderizer 20, the veneer 6 is forcedly pressed against the rotary bar 21 by the pressing belt 22, so that the veneer is bent downwardly along the small radius of curvature and many small cracks are developed in the upper part of the veneer.The degree of pressure of the pressing belt 22 against the veneer is adjusted by the air cylinder 24, in dependance on the kind of veneer and thickness thereof. In some cases where the tenderizing is not required, the piston rod of the air cylinder 24 is fully retracted to lift the pressing belt 22 to a level not contacting the veneer.

After passing through the tenderizer 20, the veneer 6 is tenderized and, thereby, flattened without curling and discharged upon a fixed discharge conveyor belt 25, from which the veneer 6 is further carried to a subsequent stage for treatment.

As the peeling of the veneer 6 from the log 7 is carried out continuously, the veneer lathe 1 is advanced forwardly toward the axis of the log and the cutting angle of the knife 2 relative to the periphery of the log is adjusted.

At the time of such advancement and adjustment of the veneer lathe 1, the movable frame pivotably connected to the veneer lathe can follow therewith without changing the length of the guide conveyor belt 12, so that the speed control of the guide conveyor belt is very easy at any advanced position of the veneer lathe.

Although the present invention has been described with reference to a preferred embodiment thereof, many modifications and alterations may be made within the scope of the present invention. For example, the tenderizer is not limited to the use of the pressing belt.

In place of the pressing belt, a roller covered with soft rubber can be used. Alternatively, a rotary member having sharp edges at the periphery thereof can be used as the tenderizer.

Claims

1. An apparatus for peeling veneer comprising a veneer lathe having a knife, a nosebar, a knife block and a nose-bar block, the knife block and nose-bar block defining a hollow space therebetween for discharging a veneer peeled from a log by said knife; a movable frame pivotably connected to said veneer lathe to move together with the movement of said veneer lathe, a guide conveyor belt supported by said movable frame and extending at an upstream portion thereof into said hollow space to define a first veneer discharge passage above the inner surface of said knife block; a tenderizer supported by said movable frame at the downstream end portion of said guide conveyor belt, and a fixed conveyor belt provided below said tenderizer for receiving the tenderized veneer to discharge said veneer outwardly of said movable frame.

2. An apparatus as claimed in claim 1, wherein said movable frame has an arm pivotably connected thereto at one end portion thereof which extends into said hollow space, said arm having a pulley at the other end portion thereof upon which said guide conveyor belt runs, said arm being elastically urged toward said nose-bar block.

3. An apparatus as claimed in claim 1 or 2, wherein said movable frame has a second conveyor belt thereon which defines a horizontal discharge passage below the downstream portion of said guide conveyor belt, the verical space of said horizontal discharge passage becoming narrower toward the downstream end thereof.

4. An apparatus as claimed in any one of claims 1 to 3, wherein said tenderizer comprises a rotary bar having a small radius of curvature and supported on said movable frame below the downstream end portion of said guide conveyor belt and a pressure means for pressing the veneer against said rotary bar to bend said veneer downwardly.

5. An appartus for peeling veneer substantially as herein described with reference to and as illustrated in the accompanying drawings.